Impact of lymphopenia and hypogammaglobulinemia on outcomes in neutropenic patients with hematological malignancies

Neutropenic patients with hematological malignancies are at high risk for infectious complications. Whether associated lymphopenia or hypogammaglobulinemia further increase this risk and affect outcome remains unclear. This retrospective single-center study included 321 patients hospitalized with lymphoma or leukemia and severe neutropenia whose serum immunoglobulin levels were measured. Overall, 60% of patients had isolated lymphopenia, 9% isolated hypogammaglobulinemia, 24% both, and 7% none. There was no correlation between absolute lymphocyte count and IgG. Severe lymphopenia was not associated with infection or mortality. Hypogammaglobulinemia was more prevalent in lymphoid leukemias and lymphomas. A multivariate logistic regression analysis adjusting for age, underlying hematological malignancy, absolute neutrophil and lymphocyte counts, and duration of neutropenia and lymphopenia showed that hypogammaglobulinemia was associated with infection (OR 1.85, 95% CI 1.07-3.26, p = 0.03), pneumonia (OR 2.04, 95% CI 1.13-3.72, p = 0.02), and sepsis or septic shock (OR 2.43, 95% CI 1.26-4.72, p = 0.01). This indicates a need for further investigation into the role of immunoglobulin replacement therapy in this setting.